B. Mangiavillano

Intraductal optical coherence tomography for investigating main pancreatic duct strictures

BACKGROUND AND STUDY AIMS:Optical coherence tomography (OCT) permits high-resolution imaging of tissue microstructures using a probe that can be inserted into the main pancreatic duct (MPD) through a standard endoscopic retrograde cholangiopancreatography (ERCP) catheter. This prospective study was designed to assess the diagnostic capacity of OCT to differentiate between nonneoplastic and neoplastic lesions in patients with MPD segmental strictures.PATIENTS AND METHODS:Twelve consecutive patients with documented MPD segmental stricture were investigated by endoscopic ultrasonography (EUS), with fine-needle aspiration cytology if necessary, and ERCP, followed by brush cytology and OCT scanning.RESULTS:OCT recognized a differentiated three-layer architecture in all cases with normal MPD or chronic pancreatitis, while in all the neoplastic lesions the layer architecture appeared totally subverted, with heterogeneous backscattering of the signal. The accuracy of OCT for detection of neoplastic tissue was 100% compared with 66.7% for brush cytology. In one case, neither OCT scanning nor brush cytology was possible because of the severity of the stricture.CONCLUSIONS:This pilot study showed that OCT is feasible during ERCP, in cases of MPD segmental stricture, and was superior to brush cytology in distinguishing nonneoplastic from neoplastic lesions.

Optical coherence tomography in pediatric patients: A feasible technique for diagnosing celiac disease in children with villous atrophy

BACKGROUND AND AIMnCeliac disease is a common condition with many atypical manifestations, where histology serves as the gold standard for diagnosis. A useful new technique, optical coherence tomography, can depict villous morphology in detail, using light waves. This study examined the correlation between the sensitivity and specificity of optical coherence tomography in pediatric patients undergoing esophago-gastro-duodenoscopy for the diagnosis of celiac disease.nnnMATERIALS AND METHODSnA total of 134 children were prospectively enrolled, 67 with a serological suspicion of celiac disease (group 1) and 67 with negative histology for celiac disease (group 2). During a diagnostic esophago-gastro-duodenoscopy we acquired multiple images and films in the four quadrants of the second part of the duodenum, and biopsies were taken in the area where optical coherence tomography had been done. Three patterns of villous morphology were considered: pattern 1=no atrophy (types 0, 1 or 2 of the Marsh classification); pattern 2=mild atrophy (type 3a or 3b); pattern 3=marked atrophy (type 3c).nnnRESULTSnThe diagnosis of celiac disease was histologically confirmed in all 67 children with positive antiendomysium and/or antitransglutaminase antibodies. Optical coherence tomography correlated with pattern 1 histology in 11/11 cases, pattern 2 in 30/32 (93.8%) and pattern 3 in 22/24 (91.6%). Sensitivity and specificity were 82% and 100%. In the control group there was 100% concordance between optical coherence tomography and histology. The overall concordance between optical coherence tomography and histology in determining patchy lesions was 75%.nnnCONCLUSIONnOptical coherence tomography could be a helpful diagnostic tool in children with mild or marked villous atrophy for diagnosing celiac disease during upper gastrointestinal (GI) endoscopy, avoiding biopsies. However, duodenal biopsies are mandatory if the optical coherence tomography shows normal villous morphology in patients with positive antibodies.

EUS-guided rendezvous technique for difficult cannulation of an intradiverticular papilla

quent finding, encountered in 5±23 % of endoscopic retrograde cholangiopancrea− tography (ERCP) procedures [1]. When present, it can make cannulation of the common bile duct difficult, especially if the papilla is located deep in the diverti− culum [2]. A 69−year−old woman was re− ferred to our center for a second attempt at performance of ERCP after an earlier failure caused by a big duodenal diverti− culum with a deeply located papilla. The patient had a diagnosis of intrahepatic abscess between hepatic segments VII and VIII, which had been unsuccessfully treated by antibiotic therapy and percuta− neous drainage. With the patient under deep sedation (propofol) we tried to can− nulate the papilla, but our attempt too was unsuccessful. An endoscopic ultra− sound (EUS)−guided rendezvous drainage of the bile duct was performed (FG 36UX echoendoscope; Pentax GmbH, Hamburg, Germany), puncturing the common bile duct with a 22G needle (EUSN 1; Wil− son±Cook, Winston Salem, NC, USA) (l Fig. 1). A 0.018−inch guide wire (Path− finder; Boston Scientific, Natick, MA, USA) was passed through the needle until it reached the duodenum (l Fig. 2). Using a duodenoscope (ED 3480TK; Pen− tax), the wire was captured with a snare (l Fig. 3) and a 2−mm sphincterotome was placed over the wire (l Fig. 4). After sphincterotomy a 7−Fr pigtail nasobiliary drain was placed for drainage of the bile ducts. EUS−guided rendezvous technique for difficult cannulation of an intradiverticular papilla

Optical coherence tomography in the diagnosis of coeliac disease: a preliminary report

Coeliac disease (CD) is a common condition with many atypical manifestations and an estimated worldwide prevalence of 1 in 266.1 It often goes unrecognised because characteristic histopathological abnormalities must be found to confirm the diagnosis. Endoscopic signs of CD are described in the literature but cannot be relied upon for detection of the disease because their sensitivity and specificity are not high. To investigate CD in every patient undergoing oesophagogastroduodenoscopy (OGD) for dyspeptic symptoms is not realistic, especially if we consider the significant costs of histological handling. Therefore, a way of detecting CD is selection of patients in which biopsies of the duodenal mucosa must be performed.nnA useful new medical technique, optical coherence tomography (OCT), that combines the principles of ultrasound and infrared backscattering light, …

Investigation of Oddi sphincter structure by optical coherence tomography in patients with biliary-type 1 dysfunction: A pilot in vivo study

BACKGROUNDnType 1 sphincter of Oddi dysfunction is a clinical entity characterised by biliary-type pain, elevated liver biochemical tests, and common bile duct dilation. Sphincter fibrosis is a common finding in this type of dysfunction and may require in some cases a differential diagnosis with a malignant intra-papillary disease. Optical coherence tomography permits high-resolution, real-time imaging of the sphincter of Oddi microstructure by a probe inserted into the common bile duct through an ERCP catheter. No data exist on the evaluation of sphincter of Oddi fibrosis by optical coherence tomography during ERCP in vivo.nnnOBJECTIVEnTo assess the feasibility of optical coherence tomography investigation of the sphincter of Oddi structure and assess its potential for diagnosing type 1 sphincter of Oddi dysfunction.nnnPATIENTSnTen consecutive patients, five with biliary-type 1 sphincter of Oddi dysfunction and five with pancreatic head/mid-body adenocarcinoma not involving the papillary region, who underwent both endoscopic ultrasound and therapeutic ERCP, were investigated by optical coherence tomography immediately before biliary sphincterotomy or stenting.nnnRESULTSnIn all sphincter of Oddi dysfunction patients optical coherence tomography recognised a hyper-reflective intermediate, fibro-muscular layer, significantly thicker than in patients with non-pathological sphincter of Oddi (p<0.0001).nnnCONCLUSIONSnOptical coherence tomography imaging recognised an increased thickness and reflectance of the fibro-muscular layer of the sphincter of Oddi, very likely determined by fibrosis, and was not time-consuming; it can be safely used during ERCP to confirm the diagnosis in difficult cases. Its use in clinical practice has one important limitation since it requires magnification in the post-procedure computer analysis to obtain images useful for diagnosis.

Preliminary data on the use of intraductal optical coherence tomography during ERCP for investigating main pancreatic duct strictures

Optical coherence tomography (OCT) is an optical imaging technique that uses infrared light reflectance and produces high resolution microstructural cross sectional images of tissues in vivo.1–3 The OCT probe can be inserted inside a standard transparent endoscopic retrograde cholangiopancreatography (ERCP) catheter. To date, only the epithelium of the main pancreatic duct (MPD) has been examined by OCT in humans in three studies: one post mortem4 and two ex vivo.5,6 The aim of the present prospective pilot study was to assess the feasibility of intraductal OCT in vivo during an ERCP procedure, its ability to identify changes in MPD wall structure in vivo, and its ability to differentiate non-neoplastic from neoplastic tissue in the presence of MPD strictures.nnFifteen consecutive patients with documented or suspected MPD strictures …

Usefulness of lower gastrointestinal endoscopy on suspicion of an iatrogenic sigmoid perforation caused by an aorto-bifemoral prosthetic bypass.

6.0 % of patients who undergo aortic sur− gery and is associated with a high mortal− ity rate (20 ±75 %) [1]. Vascular−enteric fistulas (VEF) most commonly involve the third or fourth portion of the duode− num (87 % of cases), rarely the colon (2%) [2, 3]. A 76−year−old man was admitted to our institution because of sepsis, most likely induced by graft infection. The patient had received an aorto−bifemoral bypass for treatment of an abdominal aortic an− eurysm 10 months earlier. The postopera− tive course was characterized by sepsis (Pseudomonas aeruginosa). Before admis− sion the patient reported episodes of rec− torrhagia; angio−CT showed that the left graft limb had perforated straight through the sigmoid colon. Colonoscopy allowed the vascular stent to be located in the sigmoid colon (l Fig. 1, 2). The proximal and distal extremities of the stent were not recognizable, since the stent had migrated into the extraluminal compartment. Exploratory surgery was conducted and revealed that the vascular stent had become displaced through the distal sigmoid colon, leading to perfora− tion of the wall. The affected part of the sigmoid was resected together with the graft limb, with creation of a temporary Hartmann’s diversion. We suggest per− forming lower gastrointestinal endosco− py early on suspicion of VEF in patients who have had a vascular stent placed and who present recurrent infectious epi− sodes and low gastrointestinal bleeding of unexplained origin.